Tarnishproof cloth



Patented oct. 31, 1933 T QFFEC TARNISHPROOF CLOTH Walter G. Aurand, Wallingford, Conn., assignor to R. Wallace & Sons Mfg. Co., Wallingford,

Conn.

Application July 8, 1932. Serial No. 621,365

2 Claims.

My invention relates to a novel type of textile fabric for use in wrapping, in lining boxes or otherwise to protect articles having a metal surface subject to tarnishing. While I am aware 5 that other types of salts have been employed to impregnate textile fabrics for the above purpose,

I have discovered that if a textile fabric be impregnated with a cadmium salt, preferably one of the relatively soluble salts such as cadmium acetate that it will function to prevent the tarnishing of the metal surface in a much more efiicient manner than any other article of which I am aware. One advantage of employing such a salt is that I have found .that cadmium salts have a greater amnity for free sulphur, the chief cause of tarnishing, than the metal surface of the article covered. It is well known that free sulphur or sulphur in the form of hydrogen sulphide is apt to be present in the air and is '20 the chief cause of tarnishing metal surfaces. I

have found out in practice from numerous tests that cadmium has a greater aiiinity for said sulphur than other substances of which I am aware. A further advantage of employing a cadmium salt is that improved textile fabrics may be dyed various shades of colors and as the sulphur combines with the cadmium salt it forms merely a cadmium sulphide of a light yellow color which does not affect to any appreciable 3o extent the color of the dyed fabric. I believe therefore that'I have provided a textile fabric impregnated with a tarnish proof substance which may be dyed a large variety of shades and in which the color will not be affected by tarnishing agents.

Afurther advantage in using cadmium is that as the salts of cadmium crystallize they tend to form relatively smaller crystals which tend to be intimately impregnated into the poresof 40 the textile fabric and ll up the interstices between adjacent strands of fabric or libres. I believe the action is rather analogous to the rust proofing of articles with cadmium salts in that the crystals tend to form in close association on the fabric toperforman additional function of shutting out the air in addition to of themselves absorbing the sulphur fumes.

The drawingis a perspective view of a fabric impregnated with a suitable tarnish proong cadmium salt.

For the purpose of my invention I take any suitable type of a textile fabric designed for the Wrapping or packing material, preferably a pile or a napped fabric such as velveteen or duvetyn and treat it in any suitable manner with a suitable bath, preferably containing a cadmium salt in partial or entire solution therein. While any one -of the more or less soluble types of cadmium salts may be' employed, I preferably employ one of the more soluble salts such as cadmium ace tate. While I preferably passthe cloth through a bath containing the cadmium acetate in solution it is apparent that if desired, the solution may be merely poured or sprayed over the fabric or the fabric may be dipped therein. I obtain satisfactory results by passing the material through a bath made up of one-half lb. of cadmium acetate toa gallon of water which, however, may be either strengthened or further diluted if desired. The application of the tarnish proofing cadmium salt is preferably made after the usual dyeing operation and hence does not in any manner affect the type of dye which may be put upon the fabrics. In addition, as sulphur attacks the fabric cadmium sulphide is formed, a light yellow and insoluble substance which does not materially affect even the lightest shades of dye. This is quite anadvantage over other sulphides such as silver or lead which tend to strongly discolor any dyed fabric as the sulphide forms in use.

It is understood that my invention is not limited to the specific product vdescribed and that various deviations may be made therefrom Without departing from the spirit and scope of the appended claims.

What I claim is:

1. An article of manufacture for protecting articles having a metal surface subject to tarnishing consisting of dyed textile fabric impregnated with cadmium acetate.

2. The improved process of making a tarnishproof material for use in wrapping and the like articles which are subject to tarnishing, which comprises, dyeing aktextile fabric and impregnating the fabric with a cadmium salt.

WALTER G. AURAND. 

